48
[SwitchA] mpls ldp
[SwitchA-ldp] advertise-label prefix-list prefix-to-b peer peer-b
[SwitchA-ldp] quit
# On Switch C, create IP prefix list
prefix-to-b
to permit subnet 21.1.1.0/24. Switch C uses this
list to filter FEC-label mappings advertised to Switch B.
[SwitchC] ip prefix-list prefix-to-b index 10 permit 21.1.1.0 24
# On Switch C, create IP prefix list
peer-b
to permit 2.2.2.9/32. Switch C uses this list to filter
peers.
[SwitchC] ip prefix-list peer-b index 10 permit 2.2.2.9 32
# On Switch C, configure a label advertisement policy to advertise only the label mapping for
FEC 21.1.1.0/24 to Switch B.
[SwitchC] mpls ldp
[SwitchC-ldp] advertise-label prefix-list prefix-to-b peer peer-b
[SwitchC-ldp] quit
# On Switch D, create IP prefix list
prefix-to-a
to deny subnet 21.1.1.0/24. Switch D uses this
list to filter FEC-label mappings to be advertised to Switch A.
[SwitchD] ip prefix-list prefix-to-a index 10 deny 21.1.1.0 24
[SwitchD] ip prefix-list prefix-to-a index 20 permit 0.0.0.0 0 less-equal 32
# On Switch D, create IP prefix list
peer-a
to permit 1.1.1.9/32. Switch D uses this list to filter
peers.
[SwitchD] ip prefix-list peer-a index 10 permit 1.1.1.9 32
# On Switch D, create IP prefix list
prefix-to-c
to deny subnet 11.1.1.0/24. Switch D uses this
list to filter FEC-label mappings to be advertised to Switch C.
[SwitchD] ip prefix-list prefix-to-c index 10 deny 11.1.1.0 24
[SwitchD] ip prefix-list prefix-to-c index 20 permit 0.0.0.0 0 less-equal 32
# On Switch D, create IP prefix list
peer-c
to permit subnet 3.3.3.9/32. Switch D uses this list to
filter peers.
[SwitchD] ip prefix-list peer-c index 10 permit 3.3.3.9 32
# On Switch D, configure a label advertisement policy. This policy ensures that Switch D does
not advertise label mappings for FEC 21.1.1.0/24 to Switch A, and does not advertise label
mappings for FEC 11.1.1.0/24 to Switch C.
[SwitchD] mpls ldp
[SwitchD-ldp] advertise-label prefix-list prefix-to-a peer peer-a
[SwitchD-ldp] advertise-label prefix-list prefix-to-c peer peer-c
[SwitchD-ldp] quit
354B
Verifying the configuration
# Display LDP LSP information on each switch.
[SwitchA] display mpls ldp lsp
Status Flags: * - stale, L - liberal, B - backup
FECs: 2 Ingress: 1 Transit: 1 Egress: 1
FEC In/Out Label Nexthop OutInterface
11.1.1.0/24 1277/-
-/1151(L)
-/1277(L)
21.1.1.0/24 -/1276 10.1.1.2 Vlan-int2
1276/1276 10.1.1.2 Vlan-int2
[SwitchB] display mpls ldp lsp
Status Flags: * - stale, L - liberal, B - backup